Benki → All Posts

How to use Yomitan on Android

1. Install and open Microsoft Edge Canary.
2. On the browser’s about page, which you can find in the settings menu, tap the build number 5 times to enable developer mode.
3. In the developer mode settings, select extension install by ID and input idelnfbbmikgfiejhgmddlbkfgiifnnn.

The extension ID is found as the last part of the URI of the Yomitan extension page in the Microsoft Edge add-on store.

You can combine Yomitan with ッツ Ebook Reader to read ePub books with dictionary support. This makes extra sense when the Android device is a Boox ebook reader.

Apple’s virtualization framework and APFS compression do not like each other

The setting: You are running a virtualized GNU/Linux instance on an Apple computer. You are in an APFS folder shared with the guest by way of the virtiofs support built in to Apple’s virtualization framework.

Compress a file (any compressible file, but it helps if it has at least a few non-zero bytes in it or the effect will not be particularly impressive) on the host:

host$  afsctool -vc -T LZFSE example.txt

Make a copy of the file using GNU cp inside the guest:

guest$  cp example.txt copy.txt

Observe that the copy contains only zeros:

guest$  od copy.txt
0000000 000000 000000 000000 000000 000000 000000 000000 000000
*
0016020 000000 000000 000000 000000
0016027

Digging deeper using strace, observe that in the cp run, lseek(3, 0, SEEK_DATA) fails with ENXIO (which indicates that the file is sparse and consists of a single big hole) when the correct return value would be 0:

openat(AT_FDCWD, "example.txt", O_RDONLY) = 3
...
lseek(3, 0, SEEK_DATA) = -1 ENXIO (No such device or address)

The assumptions that GNU cp makes seem to be in line with the specifications of the system calls involved. I infer that there must be a bug somewhere between Linux’s virtiofs driver, Apple’s virtualization framework, and APFS.